SPSS® 12.0 Command Syntax Reference

Nested DO IF Structures
DO IF 499
To perform transformations involving logical tests on two variables, you can use nested
DO IF—END IF structures.
• There must be an END IF command for every DO IF command in the structure.
Example
DO IF (RACE EQ 5). /*Do whites
+ DO IF (SEX EQ 2). /*White female
+ COMPUTE SEXRACE=3.
+ ELSE. /*White male
+ COMPUTE SEXRACE=1.
+ END IF. /*Whites done
ELSE IF (SEX EQ 2).
COMPUTE SEXRACE=4.
/*Nonwhite female
ELSE.
COMPUTE SEXRACE=2.
/*Nonwhite male
END IF. /*Nonwhites done
• This structure creates variable SEXRACE, which indicates both the sex and minority status
of an individual.
• An optional plus sign, minus sign, or period in the first column allows you to indent
commands so you can easily see the nested structures.
Complex File Structures
Some complex file structures may require you to imbed more than one DATA LIST command
inside a DO IF—END IF structure. For example, consider a data file that has been collected
from various sources. The information from each source is basically the same, but it is in
different places on the records:
111295100FORD CHAPMAN AUTO SALES
121199005VW MIDWEST VOLKSWAGEN SALES
11 395025FORD BETTER USED CARS
11 CHEVY 195005 HUFFMAN SALES & SERVICE
11 VW 595020 MIDWEST VOLKSWAGEN SALES
11
12
CHEVY 295015
CHEVY 210 20
SAM’S AUTO REPAIR
LONGFELLOW CHEVROLET
9555032 VW HYDE PARK IMPORTS
In the above file, an automobile part number always appears in columns 1 and 2, and the automobile
manufacturer always appears in columns 10 through 14. The location of other information,
such as price and quantity, depends on both the part number and the type of automobile.
The DO IF—END IF structure in the following example reads records for part type 11.